Alerting listeners to a lost Britain … Public Service Broadcasting. Photograph: Richard Andrews

The credits on the debut album by London duo Public Service Broadcasting mark it out as a unique prospect: it's fairly safe to say Inform-Educate-Entertain will be the only album this year to feature guest appearances by Marie Slocombe, a temporary secretary at the BBC in the 1930s who ended up founding the BBC Sound Archive by accident, or Thomas Woodrooffe, Royal Navy lieutenant commander, author of Vantage at Sea: England's Emergence as An Oceanic Power and commentator at the Berlin Olympics.

The duo's raison d'etre is to trawl through old film archives – those of the GPO Film Unit seem to be a favourite – in search of snippets of voices to set to music. It seems a pretty arcane pursuit, but it's without precedent or in isolation. As the album plays, listeners with long memories may find themselves recalling a period in the mid-80s when it was briefly held that the dernier cri in forward-thinking rock and pop music was to overlay your song with sampled snatches of film dialogue: the era of Big Audio Dynamite's E=MC2, Paul Hardcastle's 19, and Steinski and the Mass Media's We'll Be Right Back; of Keith Le Blanc and Tackhead's experiments on the On-U Sound label, and of Colourbox, whose frantic Just Give 'Em Whisky is occasionally and presumably unconsciously evoked by Inform-Educate-Entertain, not least on Signal 30, which samples a variety of aged US road safety films over raging guitars.

On another level, it has something at least spiritually in common with both British Sea Power (there's a parallel between Public Service Broadcasting's live shows, where they perform before a bank of old TV sets showing manipulated footage from the films, and British Sea Power's performances accompanying films such as Robert Flaherty's Man of Aran or Penny Woolcock's From the Sea to the Land Beyond) and the hauntological electronica released on the GhostBox label. But while GhostBox artists largely concentrate on evoking memories of the childhood dread induced by 70s public information films or eerie old kids' TV series – giving listeners of a certain age the creeps by reminding them, as the writer Rob Young brilliantly put it, of "a country and an age that have now disappeared, but its aural and visual traces make us realise, too late, that we were once actively living there ourselves" – the music made by Public Service Broadcasting isn't creepy at all. That's partly because the voices are from an age that no one listening is likely to remember, unless Public Service Broadcasting have a cadre of nonagenarian fans, all nodding in mutual recognition at the appearance Thomas Woodrooffe, commentating on a royal inspection of the naval fleet in 1937 on the dreamlike Lit Up. But it's mostly because there's usually something strangely uplifting about the taut, Neu-inspired rock that is Public Service Broadcasting's main musical setting.

Their interest seems to be in alerting listeners to a lost Britain that certainly seems strange – "it's fairyland, the whole thing is fairyland" repeats an audibly drunk Woodrooffe, over and over again – but never sinister.

Or, at least, on the surface. Most of the voices sampled here come from propaganda films. However artful and evocative they seem today, they weren't really films about Britain so much as films about controlling people. At its least interesting, Inform-Educate-Entertain seems to avoid addressing that fact in favour of simply wallowing in a kind of fusty Keep Calm and Carry On nostalgia, a sensation heightened when pseudonymous frontman J Willgoose reaches for a banjo instead of his keyboard. But the moments when you fear it's veering perilously close to a bunting-strewn whimsy are outweighed by those where a disquieting confusion decends. If you find yourself stirred by Spitfire – and it does sound pretty thrilling as it hurtles towards its climax, its motorik rhythm layered with a mesh of electronics and guitars that gradually drown out the dialogue from The First of the Few – are you being manipulated as readily as the original audiences of that film, designed to fill cinema-goers with nationalistic pride in the wake of the Battle of Britain? On other occasions, the voices are recontextualised. The closing Late Night Final samples What a Life!, a 1948 film intended to dispel the gloom of postwar austerity. The track doesn't bother with the film's resolution, only the complaints of its protagonist – "things have never been as bad as this … have you seen the headlines?" – drifting over mournful saxophones and synths and an endlessly repeating two-note guitar riff. "It can't go on, you know," protests one voice: it could be making a point about Public Service Broadcasting themselves. More a concept than a band, it's a little hard to see where they can go from here without repeating themselves. For now, though, Inform-Educate-Entertain is a flawed but fascinating curiosity.